1. Field of the Invention
The present invention relates to a technique effectively used for an apparatus (an information processing system, a mobile phone, a portable information processing system, etc.) having the function to display an image.
2. Description of the Related Art
In recent years, the imaging devices such as the digital camera and the apparatuses having the imaging devices (the mobile phone, PDA (personal digital assistant) or other information processing systems) have decreased in size more than ever before. With the decrease in size of these devices, the weight is reduced or otherwise the portability has been improved for the convenience of users. On the other hand, some problems have been posed by the size reduction.
Generally, an imaging device or the like has a display unit, and the user can confirm a picked-up image by displaying it on the display unit. With the reduction in size of the imaging device, however, the display unit has also been reduced in size, thereby making it difficult to confirm the details of the image picked up.
It is true that even with the display unit reduced in size, it has been possible for the user to roughly confirm the pattern, i.e. whether the image of the intended subject is successfully picked up in the image frame or not and whether the whole image is not “whitened” or not. With the conventional display unit reduced in size, however, it is difficult to confirm the details of a part of the image, i.e. whether the image of the intended subject is not blurred by the hand vibration or the intended subject opens the eyes thereof.
In the prior art, in order to solve these problems, a magnified reproduction function has been proposed. In the conventional magnified reproduction function, in response to a user instruction for magnified reproduction, an initially set position (normally, the screen center) is displayed magnified on the display unit at a predetermined magnification rate. By depressing the cursor key or the like, the user can confirm the details of the intended subject by moving the magnified portion within a predetermined range.
Nevertheless, the intended subject is not always imaged at the initially set position. In the case where the intended subject is not displayed magnified in response to the instruction for magnified reproduction, therefore, the user is required to depress the cursor key repeatedly to search for the intended subject from the magnified image. Thus, a great amount of time and labor are required to confirm the image.
To solve this problem, the technique described below is available. In imaging a subject with a digital camera, the position of a marker specifying the image area to be magnified in the whole display area of the display unit is set by a magnified area setting unit and input to an image processing unit. The image processing unit displays the marker at the input position of the display unit and specifies the image area to be magnified. Once the focusing operation is started, the image processing unit reads the whole image data stored in a frame memory and displays it in the whole display area of the display unit. Then, the image data of the image area to be magnified specified by the marker is read, magnified at a predetermined magnification rate, and displayed in the magnified display area of the display unit.
Another technique to solve the problem is available as described below. As long as the shutter button is not depressed, the whole image of a subject picked up by a two-dimensional imaging unit is displayed on a liquid crystal display unit with the resolution of the particular liquid crystal display unit. In the case where the shutter is depressed half way, on the other hand, the image picked up by the two-dimensional imaging unit in the area near the center of the focus area preset by the user is displayed in the magnified display area with a higher resolution. Also, the position of the image in the whole subject displayed in the magnified display area and the resolution of the image displayed in the image magnified display area are changed whenever required in accordance with the user operation. Once the shutter button is fully depressed, the whole image of the subject picked up by the two-dimensional imaging unit with the image-recording resolution is compression coded and recorded in a recording medium.
The imaging device, etc. reduced in size, however, has not any convenient pointing device such as a mouse. The user interface unit of these small-sized devices has never been satisfactory in operability. In the prior art, therefore, it is a bothersome job for the user to designate the position of a display frame (a marker or a magnified display area) indicating the magnified position by operating the user interface unit of the small-sized imaging device, consuming a great amount of time. Also, in the case where the subject intended by the user is different from the subject automatically displayed in magnified form (the subject on which the light is to be focused, for example), or in the case where a plurality of subjects intended by the user exist, the position of the display frame is required to be set each time, thereby posing the problem of consuming a great amount of operation time.